
class BootStrap(object):

    bootstrap_class_exclude = []

    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        for name, field in self.fields.items():
            if name in self.bootstrap_class_exclude:
                continue
            old_class = field.widget.attrs.get("class", "")
            field.widget.attrs["class"] = "{} form-control".format(old_class)
            field.widget.attrs["placeholder"] = "请输入%s" % field.label
